Remote control system



Nov. 8, 1938. G. A. BURNS REMOTE CONTROL SYSTEM 2 Sheets-Sheefl Filed Jan. 18, 1956 INVENT OR. GEORGE ARTHUR BUR/V5 BY NYC wkmw v NXQ ATTORNEY.

2 Sheets-Sheet 2 G. A. BURNS REMOTE CONTROL SYSTEM O Filed. Jan. 18, 1936 Nov. 8, 193.

Patented Nov. s, 1938 2 35 -34 5' FERN? OFFEQE REMOTE CONTROL SYSTEM George Arthur Burns, Liverpool, England, assignor to Associated Telephone & Telegraph Company, Chicago, 111., a. corporation oi Delaware Application January 18, 1936, Serial No. 59,669 In Great Britain February 13, 1935 6 Claims. (Cl. 177-353) The present invention relates to improvements to enable the operator to work the apparatus in remote control and/or indicating systems parfrom this position when desired. Contact lSKZ ticularly of the type in which circuit breakers or however is provided W break Springs to p the like at a substation may be supervised and/or vent anyefi Operation if the tWO y should 5 operated from a main station. The object of the be inadvertently Op simulteneeusly- 5 invention is to provide a simplified system of this UDO t e pe at o o t Start y, p i iv type which enables a considerable reduction in from W pe RC! of the switch RC is extended the amount of apparatus required without ma- V p s lSKl o y Springs and terially reducing the facilities offered. Wiper S 3 O the Switch SD to Operate relays CO 10 It has already been suggested to indicate the and CE n parallel. Relay CO at armatures col 10 state of the various circuit breakers or the like a d 00 extends the line circuit to the armatures by means of keys which are manually operated 0f the reversing relay R d p e relay C to the appropriate position in response to an preparatory to the transmission of the selecting alarm signal indicating lack of correspondence impulses to the Substation Relay CE t a mawith the position of the associated piece of appatllfe C65 energizes e v g m g et SDM 0f 15 ratus. In this arrangement however continuthe Sending Switch SD n at arm ture ceZ conously rotating switches were used and difierent nects p ve to the pp r i n r? p n switch positions were employed for the operating energizing h m t D opens h interrupter and checking circuits. springs sdm to release relay CE which in turn According to one feature of the invention fur- Opens t Circuit o t e magnet nd on the 20 ther simplification is effected by arranging that release of themasnet armature the W p S the position of circuit breakers or the like at a t 3133 are rotated t0 the secondposition- In substation is indicated at the main station by this position relay SS is p t v W p r keys associated with a rotary switch which is set SDZ from positive, Over the Circuit previously in operation whenever a piece of apparatus traced Over Wiper RC! d t a u e 88 looks 25 changes its position, said keys operating suitable p and at armature 882 p p s a C euit for contacts and indicating by their appearance the relay While Ov W pe SD3 an alternative position of the associated apparatus. circuit is provided from positive on the bank According to another feature of the invention eommoning for the relays C0 a d C A alterthe position of circuit breakers or the like at a n e a i n th refore ak s pl ce between relay 30 substation is indicated at the main station by GE and the driving magnet SDM to effect the keys each controlling contacts associated with a automatic rotation of the wipers of the switch single position in two banks of a rotary switch SD, and for each step of the switch a positive and indicating by its appearance the position of Pulse is Conneeted y y Of a m t e Ce t0 the the associated apparatus. upper line conductor extending to the substation. 35

The invention will be better understood from As soon as the wipers reach the position corthe following description of one method of carryp d g 0 h Setting of the w c SL L for ing it into efiect reference being had to the 'instance position 6 as shown, wiper SDI encounaccompanying drawings comprising Figs. 1 and 2 ters positive through springs ISKZ of key lSK -10 which should be arranged side by side to form which operates relay RV and this relay there- 40 a complete circuit. upon at armature rvl locks up to the positive Fig. 1 shows the apparatus at the main stathrough the bank of wiper SDZ and at armatures tion while Fig. 2 shows the apparatus at the subrot and T03 reverses the connections to the line. station, the two being connected together by Stepping of the switch SD continues without inmeans of a two-conductor line. I terruption but from this point positive pulses are 45 All the apparatus is normally in the position connected to the lower line conductor extending shown. When it is desired to select and operate to the substation through springs ceZ each time a circuit breaker or a tap change switch at the relay CE energizes. When the full complement substation, the rotary selecting key SLKI, Fig. 1, of impulses have been sent the wipers of the is moved by hand to the appropriate position switch SD again come into their first position 50 and the start key ISK is then operated to start where relay RV is released, but as relay SS reup the main station apparatus. A duplicate semains held, positive potential is now extended to lecting key and start key are also shown desigrelay CH through springs ssZ which operates over nated SLKZ and ZSK respectively, and these are the line circuit and at its armature chl mainlocated at the opposite end of the control panel tains relay CO operated. The metal rectifier 55 MRC is connected up in such sense as to prevent relay RV holding to the locking circuit of relay SS.

At the substation the selecting impulses are received on the magnetically polarized relays N and R connected in series, relay N responding to what will be termed normal pulses, i. e. when positive is connected to the upper line conductor and relay R responding when the polarity of the pulses is reversed.

On the first operation of relay N, the first time relay CE operated, relay IB is operated from positive through springs 121, and over the wiper SB! of the switch SB in its first position the driving magnet SAM of the switch SA is energized in series with the low resistance winding of relay CL. Relay IB at armature |b2 opens the homing circuit of the switches SA and SB and relay CL at armature 0Z2 shunts armature rsr2 to prevent the undesired opening of the line circuit.

Normal pulses incoming over the line are repeated by armature n! over the above circuit to the driving magnet of the switch SA which therefore advances its wipers SAI to SA4 to a position corresponding to the marking in the bank SDI of the sender switch at the main station. It will be understood that the bracketed conductors leading from the bank SA4 extend to interposing relays (not shown) which control the Trip and Close movements of the circuit breakers. Each of the circuit breakers or twoposition devices and the control relays respectively associated therewith may be of any desired commercial construction and for that reason only one unit has been diagrammatically illustrated at 90, which unit corresponds to the sixth ofi-normal position of the rotary switch SA.

Subsequently reversed pulses after relay RV operates are received on relay R which at armature 1"! holds relay IB and repeats the pulses over wiper SAI (which has moved to position 6) to the driving magnet SBM of the switch SB. Ac-- cordingly the magnet SBM of switch SB responds to the remainder of the impulses in the series and sets its wipers SE] to SE3 to a position complementary to those of the switch SA.

As a check on the reception of the full complement of impulses, neither more nor less, the banks of wipers SA3 and SE3 are connected together reversed, so that a circuit is only completed through them when the sum of the pulses received by the two switches corresponds to the predetermined total. More specifically, the rotary switches SA and SB have their bank contacts so connected and arranged that any selected one of the two-position devices, such, for example, as the device 90, is caused to operate only when the number of impulses making up the two impulse trains transmitted respectively to the two rotary switches noted is equal to a predetermined number. Thus, in each case and irrespective of the two-position device to be operated, a predetermined number of impulses is transmitted from the main station over the line circuit and are divided between the two switches SA and SB through the operation of the relay RV and the resulting transfer of the control from the polarized relay N to the polarized relay R. This predetermined number of impulses is, with the arrangement illustrated, twenty-five and assuming, for example, that it is desired to select the twoposition device 80, six of the twenty-five impulses are transmitted to the switch SA. If thereafter only eighteen impulses are transmitted to the switch SB, the two switch wipers SA3 and SB3 are not connected together so that the circuit for causing the operation of the two-position device 90 is held open. As a consequence, this device cannot be operated.

When relay RV at the main station releases at the end of the train of selecting pulses, relay N at the substation is rc-operated in series with relay CH at the main station and at armature nl holds relay IB and completes a series circuit over wiper SBI, armature 0Z2, wipers SA3, S133 and SA4, and over the selected conductor extending to the interposing relay controlling the operation of the circuit breaker it is desired to produce. Tripping and closing the breaker require different selections from the main station and it will therefore be clear that in general two positions are required in the bank of wiper SA4 for each breaker controlled.

Whenever a circuit breaker or tap change switch at the substation changes its position either due to control from the main station or, in the case of a breaker, automatically due to the operation of the protective gear, a common device (not shown) is operated to effect the momentary application of positive to the start lead [0 connecting with the bank ISD2 of the switch ISD. This device may take any one of a variety of well-known forms. For example, it may comprise a slow-acting relay, as indicated diagrammatically at I00, having its contacts arranged to extend positive battery to the conductor l0 when it is operated and having its operating circuit arranged to be momentarily energized when the operating element of any one of the two-position devices, such, for example, as the device 90, is moved from either of its two positions to the other. Consequently when the position of the breaker in question is changed, the momentary application of positive to lead I0 brings about the operation of relay RSR which looks by way of its armature rsrl over the bark commoning, and at armature rsrZ opens the line circuit thereby releasing relay CH at the main station and relay N at the substation. At the main station relay CH brings down relay CO which at its armatures co! and 002 connects up the I and 0 receiving relays which are polarized by means of the metal rectifiers MRA and MR3.

At the substation relay N releases relay IB which at armature lbl, Fig. 2, operates relays E and SE overthe circuit including springs rsr3, wiper ISD|, upper winding of relay SE and through springs isdm to relay E. Relay SE at its armatures eel and seZ prepares the line for the transmission of indicating pulses from the substation. Moreover at armature IM 2. selfinterrupted homing circuit is completed for the switch SA controlled by the interrupter springs cam and when the wipers arrive on the home contact the homing circuit is extended to switch SB controlled by the interrupter springs sbm. When both switches are home, positive over armature nl and its back contact is extended over the wipers SA2 and SBZ in series and armature el to the lower line conductor with the result that relay SER connected to the upper line conduc tor is operated in series with relay 0 at the main station. Relay SER at armature serl energizes the driving magnet ISDM of the switch ISD which thereupon opens its interrupter springs lsdm and releases relay E. Relay E after its slow period opens the line circuit at armature el and in turn brings down relay SER which opens the magnet circuit and on the release of the magnet armature the wipers ISD! to lSD3 are moved to the second position. In this position relay RSR is released by the opening of its energizing circuit, but as wiper ISD! is now in engagement with the bank commoning the circuit is maintained for relays E and SE. An alternate action therefore takes place between the relays E, SER and the magnet ISDM the effect of which is to rotate the wipers of the switch iSD over their bank contacts, and during this operation relay lRV, connected to wiper iSDS, tests over the bracketed conductors shown, the in or out condition of the circuit breakers or tap change switches connected thereto.

If the breaker or tap switch connected with it is out at this instant, wiper ISD3 will encounter a disconnection on the associated bracketed conductor so that relay IRV is not operated and accordingly a positive pulse is extended over the lower line conductor. If however, the breaker or tap switch is in, wiper ISD3 will encounter positive on the associated conductor which operates relay IRV whereupon at armatures lTvl and H122 the connections to the line are reversed so that a positive pulse is now applied to the upper line conductor when relay E energizes.

At the main station the indicating pulses are received on the rectifier-polarized relays I and O and repeated to the driving magnet RCM of the switch RC either by springs H or 01 which accordingly steps its wipers over their banks in synchronism with those of the switch ISD at the substation. A high resistance relay P bridged across the polarized relays I and O is operated by all indicating pulses regardless of their polarity, and serves to energize the slow release relay B which remains operated during the impulsing period and holds open the circuit of the faulty impulse lamp FIL connected to the bank of wiper RC4. During the stepping of the switch RC individual indicating lamps such as IFL connected to the various contacts in the bank of wipers RC! are lighted progressively to identify the circuit breakers connected with at the substation. A low resistance relay CB in the feed circuit to the lamps operates and looks to the alarm reset key ALR, at the same time lighting a common alarm lamp ALL and ringing a common alarm bell ALB.

Considering the impulsing circuit of the switch RC in detail, it will be seen that when positive is applied to the lower line conductor indicating the out position of a breaker, a circuit is completed at the main station through the metal rectifier MRB in the conducting direction, winding of relay 0-, indicating key INK in out position, wiper and bank RC2 to the upper line conductor, a return circuit being supplied by way of relay SER at the substation to negative. It will be appreciated that a key such as INK is provided for each circuit breaker or tap switch at the substation and it will be seen that the operation of relay 0 is only possible if the key is in accord with the indicating pulse, that is, for normal pulses in its upper or out position. The conditions are similar if the breaker is in except that owing to the operation of relay IRV a reversed pulse is sent and relay I is operated by way of wiper RC3.

When however, a pulse is produced corresponding to a breaker which has changed its position, 2e relay I or O as the case may be will be shortcircuited by the key and at the same time the rectifier in the circuit will be non-conducting. Under these circumstances relay SER at the subbreaker at the substation, the lamps and keys being, if desired, in close proximity. When the operator moves the key to the correct position, relay I or O as the case may be is again connected in circuit with relay SER at the substation which thereupon re-operates and enables the transmission of indicating pulses to recommence.

When all indicating pulses have been transmitted, the wipers of the switch ISD at the substation will again come into their first position where the circuit is opened for relays E and SE which release and open the transmitting circuit to the line. At the main station the wipers of the switch RC will also have arrived at the first position and owing to the cessation of impulsing relays P and B are released. The common alarm lamp ALL and bell ALB are out off by the momentary operation of the alarm reset key ALR which unlocks relay CB while the restoration of the start key releases relay SS. If the start key is not at once restored the operation is not prejudiced; it must be restored however before a further selection can be made from the main station.

It will be understood that in the event of a circuit-breaker changing its position automatically, transmission takes place from the substation in the manner just described. The only difierence is that since relays SS, CH and CO at the main station are not operated, the initial opening of the line circuit by armature 'rsr2 is without effect. It will be seen also that if such automatic change occurs while a train of indicating pulses is being sent, relay RSR will be re-operated and when the first indicating train has been disposed of a second will immediately be started.

If owing to a line fault the switch RC at the main station falls out of step with the switch ESD at the substation, wiper RC4 will still be in engagement with the bank commoning after pulsing has ceased and accordingly when relay B releases, the faulty impulse lamp FIL is lighted in series with the driving magnet RCM which remains inoperative in this circuit and moreover the impulse transmission cannot be restarted by operating the indicating key associated with the lighted indicating lamp.

To check whether the fault is of an intermittent nature such as extraneous induction in the line, the operator throws the check key CK which results in the substation apparatus signalling back a complete train of indicating pulses. Conveniently the last position in the bank of the switch SD is allocated for the check feature so that when the check key is operated this position is marked by the connection of positive po tential over springs 0K2 to the last contact in the bank of wiper SDI. At the same time over springs CK3 a self-interrupted driving circuit is completed for the magnet RCM of the switch RC which accordingly rotates its wipers to the home position. 'When this position is reached, positive on the wiper RCI is extended through springs cb2 over springs CKI which simulate the operation of the start key springs ISKI, and in the manner already described the apparatus now performs a selecting function to cause the switch SA at the substation to select its last position. When this has been done the operating circuit at the substation ordinarily used for controlling the circuit breakers is effective to extend positive to the common start conductor l connecting with the bank of wiper ISD2, thereby simulating the change in position of a circuit breaker. Accordingly the substation apparatus sends back to the main station a complete set of indicating pulses in the manner already described.

If the trouble has now disappeared, these will be correctly received and may be arranged to cause the lighting of a check lamp connected to the last contact engaged by wiper RCI. On the restoration of the check key and the momentary operation of the alarm release key, the apparatus is restored to normal assuming that the indicating keys correctly represent the position of the substation equipment. A special key similar to the indicating keys may be connected to the check position of the switch RC, or the appropriate springs may be directly operated by the key CK.

If however, the faulty impulse lamp FIL again lights, the fault is likely to be of a permanent nature and the line circuit must therefore receive attention.

I claim:-

1. In a remote control system, a main station, a substation, a line circuit extending between said stations, a plurality of two-position devices in said substation, an automatic switch in said substation and operative to select any one of said devices, means responsive to the operation of said switch for transmitting impulses of different polarity over said line circuit, depending upon the position of the device selected by said switch, a pair. of relays associated with said line circuit, means whereby one of said relays responds to impulses of one polarity transmitted over said line circuit and the other thereof responds to impulses of a diiferent polarity transmitted over said line circuit, a plurality of keys at said main station, each of said keys corresponding to one of said devices and being operable to either of two positions respectively corresponding to the two positions of the corresponding device, an automatic switch in said main station operated in synchronism with said firstnamed automatic switch and operative to connect the corresponding key in circuit with said relays when a particular one of said devices is selected, each of said keys including means for rendering said relays inactive when the position of the key fails to correspond to the position of the corresponding one of said devices, means for stopping the operation of said switches when said relays are rendered inactive, a plurality of signal devices individually corresponding to said twoposition devices, and means including said signal devices for indicating a disagreement between the position of any selected one of said two position devices and the position of its corresponding key.

'2. In a remote control system, a main station, a substation, a line circuit extending between said stations, a plurality of two-position devices in said substation, an automatic switch in said substation and operative to select any one of said devices, means responsive to the operation of said switch for transmitting impulses of different polarity over said line circuit, depending upon the position of the device selected by said switch, a pair of relays associated with said line circuit, means whereby one of said relays responds to impulses of one polarity transmitted over said line circuit and the other thereof responds to impulses of a differentpolarity transmitted over said line circuit, a plurality of keys at said main station, each of said keys corresponding to one of said devices and being operable to either of two positions respectively corresponding to the two positions of the corresponding device, an automatic switch in said main station operated in synchronism with said first-named automatic switch and operative to connect-the corresponding key in circuit with said relays when a particular one of said devices is selected, each of said keys including contacts for shunting the one of said relays which is responsive to impulses of the polarity corresponding to the position of the device which corresponds to the key when the position of the key disagrees with the position of said corresponding one of said devices, means including each of said relays, when shunted by any one of said keys, for stopping the operation of both of said switches, a plurality of signal devices individually corresponding to said two-position devices, and means including said signal devices for indicating a disagreement between the position of any selected one of said two-position devices and the position of its corresponding key.

3. In a remote control system, a main station, a substation, a line circuit extending between said stations, a plurality of two-position devices in said substation, an automatic switch in said substation and operative to select any one of said devices, means responsive to the operation of said switch for transmitting impulses of diil'erent polarity over said line circuit, depending upon the position of the device selected by said switch, a pair of relays associated with said line circuit, said relays being so connected and arranged that one thereof responds to impulses of one polarity transmitted over said line circuit and the other thereof. responds to impulses of a different polarity transmitted over said line circuit, a plurality of keys at said main station, each of said keyscorresponding to one of said devices and being operable to either of two positions respectively corresponding to the two positions of the corresponding device, an automatic switch in said main station operated in synchronism with said first-named automatic switch and operative to connect the corresponding key in circuit with said relays when a particular one of said devices is selected, each of said keys including means for rendering said relays inactive when the position of the key fails to correspond to the position of. the corresponding one of said devices, means for stopping the operation of said switches when said relays are rendered inactive, a plurality of signal devices individually corresponding to said two-position devices, means including said signal devices for indicating a disagreement between the position of any selected one of said two position devices and the position of its corresponding key, and means operative when a condition of disagreement between the position of a selected two-position device and the position of the corresponding key has been corrected for initiating the operation of said switches.

4. In a remote control system, a main station,

a substation, a plurality of two-position devices in said substation, a line circuit extending between said stations, a pair of oppositely poled relays connected in said line circuit, an automatic switch for successively selecting said devices, means responsive to the selection of a device for sending a pulse of one polarity over said line circuit to operate one of said relays when a selected device is in one position and for sending a pulse of another polarity over said line circuit to operate the other of. said relays when a selected device is in its other position, a plurality of keys individually corresponding to said devices and each operable to either of two positions respectively corresponding to the two positions of the corresponding device, means for associating each key with said line circuit as the corresponding device is selected, means connectingsaid keys with the relays whereby when its position corresponds to the position of the corresponding device the one of said relays is operated which responds to impulses of the polarity corresponding to the position of the said corresponding device and neither of said relays is energized when the position of the key does not correspond to that of the corresponding device, and means operative when the position of any selected device does not correspond to the position of the corresponding key for stopping the operation of said switch.

5. In a remote control system, a main station, a substation, a plurality of two-position devices in said substation, a line circuit extending between said stations, a pair of oppositely poled relays connected in said line circuit, an automatic switch for successively selecting said devices, means responsive to the selection of a device for sending a pulse of one polarity over said line circuit to operate one of said relays when a selected device is in one position and for sending a pulse of another polarity over said line circuit to operate the other of said relays when a selected device is in its other position, a plurality of keys individually corresponding to said devices and each operable to either of two positions respectively corresponding to the two positions of the corresponding device, means for associating each key with said line circuit as the corresponding device is selected, means connecting each of said keys with the relays whereby when its position corresponds to the position of the corresponding device the one of said relays is operated which responds to impulses of. the polarity corresponding to the position of the said corresponding device and neither of said relays is energized when the position of the key does not correspond to that of the corresponding device, means operative when the position of any selected device does not correspond to the position of the corresponding key for stopping the operation of said switch, a plurality of signal devices individually corresponding to said twopcsition devices, and means including said signal devices for indicating a disagreement between the position of. any selected one of said two-posiiion devices and the position of its corresponding key.

6. In a remote control system, a main station, a substation, a plurality of two-position devices in said substation, a line circuit extending between said stations, a pair of oppositely poled relays connected in said line circuit, an automatic switch for successively selecting said devices, means responsive to the selection of a device for sending a pulse of one polarity over said line circuit to operate one of said relays when a selected device is in one position and for sending a pulse of. another polarity over said line circuit to operate the other of said relays when a selected device is in its other position, a plurality of keys individually corresponding to said devices and each operable to either of two positions respectively corresponding to the two positions of the corresponding device, means for associating each key with said line circuit as the corresponding device is Selected, means connecting the keys with the relays whereby when its position corresponds to the position of the corresponding device the one of said relays is operated which responds to impulses of the polarity corresponding to the position of the said corresponding device and neither of said relays is energized when the position of the key does not correspond to that of the corresponding device, means operative when the position of any selected device does not correspond to the position of the corresponding key for stopping the operation of said switch, and means operative when a condition of disagreement between the position of a selected two-position de- 'vice and the position of the corresponding key has been corrected for initiating the operation of said switches.

GEORGE ARTHUR BURNS. 

